In military tanks the turret usually is equipped with a large ring gear which meshes with a relatively small spur gear suitably mounted within the hull; a motor is arranged to drive the spur gear, which transmits the drive force to the ring gear and turret, as described for example in U.S. Pat. No. 3,429,222 issued Feb. 25, 1969 to Whiston et al.
The weight of the turret is relatively high so that a relatively great expenditure of power is required to operate the turret at desired speeds and acceleration levels. The resultant large motors and the associated speed reducer gearing are disadvantageous in that they undesirably detract from the usable space within the tank while subtracting power that would be otherwise useful for other purposes.
The present invention seeks to provide an anti-friction worm-wheel drive that is particularly useful for efficiently transmitting a driving force from a relatively small power source to the turret of a military tank. The anti-friction drive can hopefully also be used in other worm-wheel environments where transmission efficiency is important.